<?php
/**
 * phpcr
 *
 * Copyright (c) 2009, Olivier Hoareau <hoareau.olivier@gmail.com>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *
 *   * Neither the name of Olivier Hoareau nor the names of his
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @package   phpcr
 * @author    Olivier Hoareau <hoareau.olivier@gmail.com>
 * @copyright 2009 Olivier Hoareau <hoareau.olivier@gmail.com>
 * @license   http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @since     File available since Release 0.1.0
 */

/**
 * Base class for XML loggers.
 *
 * @author    Sebastian Bergmann <sb@sebastian-bergmann.de>
 * @copyright 2009 Sebastian Bergmann <sb@sebastian-bergmann.de>
 * @license   http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @version   Release: @package_version@
 * @link      http://code.google.com/p/phpcoderatio
 * @since     Class available since Release 0.1.0
 */
abstract class PHPCR_Log_XML
{
    protected $document;

    /**
     * Constructor.
     *
     * @param string $filename
     */
    public function __construct($filename)
    {
        $this->document = new DOMDocument('1.0', 'UTF-8');
        $this->document->formatOutput = TRUE;

        $this->filename = $filename;
    }

    /**
     * Writes the XML document to the file.
     */
    protected function flush()
    {
        file_put_contents($this->filename, $this->document->saveXML());
    }

    /**
     * Converts a string to UTF-8 encoding.
     *
     * @param  string $string
     * @return string
     */
    protected function convertToUtf8($string)
    {
        if (!$this->isUtf8($string)) {
            if (function_exists('mb_convert_encoding')) {
                $string = mb_convert_encoding($string, 'UTF-8');
            } else {
                $string = utf8_encode($string);
            }
        }

        return $string;
    }

    /**
     * Checks a string for UTF-8 encoding.
     *
     * @param  string $string
     * @return boolean
     */
    protected function isUtf8($string)
    {
        $length = strlen($string);

        for ($i = 0; $i < $length; $i++) {
            if      (ord($string[$i]) < 0x80)          $n = 0;
            elseif ((ord($string[$i]) & 0xE0) == 0xC0) $n = 1;
            elseif ((ord($string[$i]) & 0xF0) == 0xE0) $n = 2;
            elseif ((ord($string[$i]) & 0xF0) == 0xF0) $n = 3;
            else   return FALSE;

            for ($j = 0; $j < $n; $j++) {
                if ((++$i == $length) || ((ord($string[$i]) & 0xC0) != 0x80)) return FALSE;
            }
        }

        return TRUE;
    }

    /**
     * Processes a list of results.
     *
     * @param array $results
     */
    abstract public function processResults($results);
}
